Cooling towers are used to cool the water and other liquids that are circulated through various systems to remove heat from those systems. Such systems are widely varied, but are typically large scale and/or industrial systems such as power plants, manufacturing plants, chemical plants, oil refineries, and large scale heating, ventilation, and air conditioning (HVAC) systems. Cooling towers are monitored routinely to confirm normal operation. This monitoring is typically done by service personnel at the site of the cooling tower or remotely by receiving data from sensors configured to detect various measurements at the cooling tower. A common issue in monitoring cooling towers is the accuracy of the sensors being used to measure characteristics of the cooling tower, related components, and substances therein. Because these measurements may be used to diagnose problems with cooling tower systems, it is important that accurate measurements are available. For example, it may be costly and perhaps even detrimental to the system being cooled by a cooling tower if a problem, such as a high pH of cooling tower water, is diagnosed based on measurements from a biased pH sensor. Steps taken to correct a detected, but inaccurately measured, pH issue may adversely affect the pH and other aspects of the cooling tower and possibly the larger system in which the cooling tower is configured.